Effect of gamma irradiation treatment at phytosanitary dose level on physiological and consumer traits of Indian ber. Part 1. Cultivar ‘Umran’

Enhancing the antioxidant system and preserving nutritional quality of Indian Ber (Ziziphus mauritiana L.) fruit following melatonin application

The Ber fruit (Ziziphus mauritiana) is both economically valuable and nutritionally rich, but maintaining its freshness after harvest remains a challenge. This study evaluates melatonin's (MT) role in preserving ber fruit (cv. Umran) quality during cold storage. Physiologically mature fruit were treated with MT (0, 25, 50, 75 and 100 μM) for 30 min at 24 ± 2 °C and stored for 28 days at 6.5 ± 1 °C with 85-90 % relative humidity. Control fruit were dipped in distilled water. Compared to control on the last day, MT (100 μM) significantly reduced ethylene evolution (28 %), respiration rate (19 %), minimized weight loss (40 %) and retained higher firmness (35 %). Treated fruit exhibited higher total soluble solids (19 %), glucose (15 %), fructose (25 %) and sucrose (16 %). MT (100 μM) also retained 51 % more ascorbic acid, 16 % higher total phenols, and 37 % greater titratable acidity while lower polyphenol oxidase activity by 24 %, mitigating peel browning. Antioxidant activity was 30 % higher and antioxidant enzyme activities of superoxide dismutase, catalase and guaiacol peroxidase were sustained at higher levels in MT (100 μM) by 53 %, 51 %, and 131 %, respectively. Multivariate analysis confirmed MT's efficacy, with PCA explaining 85.2 % of variance in quality attributes and Pearson's correlation showing a strong positive relationship between postharvest quality and antioxidant system. These findings highlight MT (100 μM) as a promising phytohormonal treatment to extend ber fruit shelf life while maintaining nutritional and sensory quality, with potential commercial applications in postharvest management.

Kadozan Chitosan Formulation Enhances Postharvest Quality of Fresh Indian Jujube Fruit

Indian jujube fruit is prone to perishing, resulting in a shorter shelf life after harvest. Kadozan is a liquid chitosan formulation that has a significant effect on fruit preservation. In order to explore its efficacy, the quality, and storability indicators of Indian jujube fruit were evaluated during storage at 15 ± 1 °C for 18 days. Results showed that Kadozan-treated fruit exhibited lower respiration rate, relative electrolyte leakage rate, weight loss, and decay index, along with higher firmness and commercially acceptable rate. Furthermore, Kadozan-treated fruit showed higher vitamin C, total sugar, titratable acid, total soluble solids, chlorophyll, and carotenoid contents, L* and h° values, but lower a* and b* values. Principal component analysis and comprehensive score revealed that Kadozan treatment helped preserve the appearance and nutritional qualities of Indian jujube fruit. The best effect was seen with 1:600 Kadozan among three concentrations (1:300, 1:600, 1:900). It was discovered that the commercially acceptable rate of 1:600 Kadozan-treated fruit was 37.5% higher than control fruit while the decay index was 30.5% lower than control fruit at 18 days. Therefore, Kadozan treatment has great substantial implications for the preservation of Indian jujube fruit, providing practical guidance for reducing its postharvest losses.

Eco-safe hot water dip alleviates antioxidant level and sensory quality of Indian jujube fruits

Indian jujube (Ber) is highly perishable climacteric fruit owing to high decay index limiting its marketability and demands interventions to prolong shelf life. Fungicides are normally used to control rot during postharvest storage, however, residues left necessitate eco-safe alternatives like hot water dipping. Mature, pre-climacteric jujubes were dipped in 45, 50 or 55 °C water for 8, 6 or 4 min, respectively and then stored at 5 °C for periodic quality evaluation. Dipping fruits in 55 °C water resulted in 32.69 and 35.27, 64.21 and 58.57, 30.41 and 30.42, 38.50 and 52.20 % lower weight loss, decay index, malondialdehyde (MDA) and electrolyte leakage, whereas 15.40 and 16.77, 19.51 and 20.48 % greater antioxidant activity and ascorbic acid respectively for Umran and Pakwhite compared to 25 °C water dip. The highest glucose, fructose, malic, citric, and tartaric acids were 23.44 ± 1.04 and 29.9 ± 0.95, 30.68 ± 1.72 and 41.17 ± 2.34 mg/100 g, 138.1 ± 6.45 and 112.97 ± 6.16, 57.49 ± 1.71 and 53.78 ± 1.90, 79.58 ± 5.1 and 65.3 ± 4.83 μg/100 g whereas lower sucrose 12.34 ± 0.94 and 16.33 ± 1.05 mg/100 g were respectively recorded in 55 °C water dipped Umran and Pakwhite fruits. High dip water temperature (55 °C) exhibited better quality with the lowest decay index and weight loss, greater membrane integrity, bioactives content and sensory acceptance scores. Hence, hot water dipping was shown to be an effective residue-free option to extend the marketable period of jujubes to capture distant markets.